Cutting and grooving tool



May 6, 1958 D. w. BUTLER CUTTING AND GROOVING TOOL Filed 001:. 29, 1956 INVENTOR B u ZZ e r BY 24- 1 fiw z ATTORNEY CUTTING AND GROOVING TOOL Dessel W. Butler, Mount Vernon, Ohio Application October 29, 1956, Serial No. 618,723 3 Claims. c1. 30-293 This invention relates to a novel tool primarily adapted for use in accurately cutting hard materials such as Masonite, pressed asbestos, Transite, fiexiboard, and various plastics, which materials cannot be readily sawed without quickly dulling the saw.

A primary object of the present invention is to provide a tool of this character having novel means for accommodating the cuttings which are usually in a fine form.

Still a further object of the invention is to provide a tool of the aforedescribed character which may be used for accurately grooving the aforementioned materials and various other materials.

Other objects and advantages of the invention will hereinafter become more fully apparent from the follow ing description of the drawing, illustrating a presently preferred embodiment thereof, and wherein:

Figure l is a side elevational view, partly in vertical section, of the tool; 7

Figure 2 is an enlarged cross sectional view thereof, taken substantially along a plane as indicated by the line 22.0f Figure l;

Figure 3 is a fragmentary longitudinal sectional view of a portion of the tool, taken substantially along a plane as indicated by the line 3-3 of Figure.2,and

Figure 4 is a cross sectional view through apart of the tool, taken substantially along a plane as indicated by the line 44 of Figure 3.

Referring m'ore'specifically to the drawing, the cutting and grooving tool in its entirety and comprising the invention is designated generally 6 and includes anelongated stock, designated generally 7. The stock 7 includes corresponding coplanar bottom portions 8 which extend from end-to-end of the stock and which are disposed in laterally spaced relation to one another and which are connected to one another by an elongated intermediate portion 9 of the stock 7 which is of arch shaped cross section. Said arch shaped intermediate portion 9 includes a substantially flat top wall 10 which extends from end-to-end of the stock 7 and side walls 11 which are supported on and rise from the bottom portions 8, adjacent the inner edges thereof, and which bear against the underside of the top wall 10, adjacent its longitudinal side edges. 'The side walls 11 are shown connected to the bottom portions 8 and the top wall 10 by fastenings 12. However, the parts 8, 10 and 11 may be formed integral with one another. The stock 7 also includes corresponding side walls 13 which extend upwardly from the outer edges of the bottom portions 8 and which are preferably formed integral therewith. The side walls 13 extend from end-to-end of the stock and preferably have their upper edges disposed above the evel of the top wall 10.

A rear handle 14 is fixed to and rises from one end of the top wall 10 and is disposed at a rear end of the tool 6, and a knob 15 is suitably secured to and rises from the opposite end of the top wall 10. The handle 14 is adapted to be grasped with one hand and the nited States Patent 0 knob 15 is g Pped with the other hand for operating the tool 6.

A post 17 is suitably secured as by fastenings 16, one of which is shown in Figure 3, to the upper side of the top wall 10, between the handle 14 and knob 15, and extends upwardly from said top wall 10 at an incline toward the handle 14. An opening 18 is formed in the top wall 10 and extends forwardly from the lower end of the post 17 toward the knob 15. The post 17 includes a front bar 19 and a pair of laterally spaced spacer bars 20 which are secured to one another and to a part of the post 17 which is fastened to the wall 10, by fastenings 21, and which combine to form a guideway or bore 22 of noncircular cross section, a lower end of which opens through a rear end of the opening 18, and which is provided with an open upper end, as best'seen in Figure 3. The upper ends of the bars 19 and 20 terminate below the level of the upper end of the portion of the post 17 which is fixed to the wall 10, and a top plate 23 is secured, as by fastenings 24, to said stationary part of the post 17 and has a portion overlying and spaced from the upper ends of the bars 19' and 20. A feed screw 25 extends threadedly through said portion of the plate 23 and has a lower end extending loosely into the upper end of the bore 22, as seen in Figures'Z and 3. Said feed screw 25 has a knurled head 26 at its upper end by means of which the feed screw may be turned with the thumb .and fingers. The front plate or bar 19 is beveled on its forward side and its lower end, as seen at 27.

An elongated cuttingbit 28 includes an elongated shank 29 of rectangular cross section which fits slidably in the guideway or bore 22 and which has an upper end bearing against the lower end of the screw 25. As best seen in Figure 2, one side wall of the shank 29 has an elongated recessed portion 30 which terminates at points spaced from the ends thereof. -A screw 31 is threaded inwardly through one of the spacer bars 20- and has an inner end which can be advanced sutn'ciently into the bore 22 to engage loosely in the recessed portion 30 of the bit shank 29. The screw 31 is spaced slightly'from the bed of the recess 30 to permit an unimpeded limited sliding movement of the bit in the bore 22 but is adapted to engage therends of the recessed portion 30 to prevent complete removal of the bit 28 from the bore 22 through the lower end thereof and to limit upward movement of the bit in said bore, when the screw 31 is in a fully advanced position as seen in Figure 2. A screw 32 is threaded into the front plate 19 and anchors one end of a spring 33 against the outer side of said front plate. An opposite end of the spring 33 extends into the bore 22 through an opening 34 of the frontplate and yieldably bears against the bit shank 29 to retain the bit against free sliding movement in the bore 22. The upper end of the forward side of the shank 29 is beveled as seen at 35 for camming the spring 33 outwardly of the bore 22 as the bit 28 is inserted upwardly through said bore.

The lower end of the bit 28 is recessed on opposite sides thereof to form a cutting and grooving blade or knife 36, the side walls of'which converge relative to one another from the forward face 37 to the rear face 38 thereof, so that the forward face 37 is wider than the rear face. A bottom edge 39 of the knife 36 is disposed at an acute angle to the front face 37 and is inclined slightly upwardly toward the back face 38, when the bit 28 is mounted in the post 17, as best seen in Figures 1 and 3. Said bot tom edge combines with the front face 37 to form the cutting edge 40 of the knife 36, which is formed by the apex of the face 37 and edge 39.

The feed screw 25 is manually adjusted to displace the bit 28 downwardly until the cutting edge 40 thereof Patented May 6, 1958 is, disposed at a desired level beneath the bottom surface of the stock 7, as defined by the coplanar bottom-faces of the bottom portions 8. When thus disposed, the tool 6-ifmanipulated manually utilizing both hands,-as previously described, will cause the cutting edge 40 to cut a groove in a piece of material to a desired: depth, in combination with the longitudinal side edges of the front face 37 of the knife'3fi, which constitute'additional cutting edges 41 for cooperation with the-bottom cutting edge 49. Where the tool 6 is utilized for cutting com pletely through a piece of hard material, the cutting edge 40 is adjusted downwardly-to below the bottom surface of the stock 7 to an extent greater than" the thickness of post a cutting bit including a shank adjustably mounted in the tool post, said cutting bit having a recessed lower end portion defining a cutting blade extending downwardly through the top Wall opening and through a portion of said groove, said blade having a relatively narrow the material, sothat a complete cut or 'severence of the 7 material will be accomplished. The bit 28 is formed of high carbon steel whichwill cut hard materials without being-dulled readily. Theopening 18 is provided so that the cutting edges 40 and 41 will be visible to the operator during the cuttingoperation and the beveled surface 27 is also provided [or this purpose, so that an accurate cutting or grooving operation can be accomplished. I

In cutting hard materials, such as asbestos shingles, Masonite and the like, the cuttings will be in the form of fine small pieces rather than long shavings and which are incapable of escaping through the opening 18. Accordingly, to prevent such cuttings from clogging the tool and obstructing its proper operation, the stock 7 is provided with the arch shaped intermediate portion 9 which forms a downwardly opening groove or channel 42 which extends from end-to-end of the stock and in which the cuttings are accommodated on either side of the knife 36. Without the groove 42 efiicient operation of the tool 6 in the aforedescribed manner for either cutting or grooving of hard materials cannot be efiectively accomplished.

Various modifications and changes are contemplated and may be resorted to without departing from the function or scope of the invention as hereinafter defined by the appended claims.

I claim as my invention:

1. A cutting and grooving tool of the character described comprising an elongated stock having laterally spaced coplanar bottom portions extending from end-toend thereof and an elongated intermediate portion of arch shaped cross section extending from end-to-end of the stock and connecting said bottom portions, said interforward face including sharpened side edges disposed between and spaced from the sides of the groove and a sharpened lower end adjustably positioned below the level of said bottom portions of the stock, said side edges and lowerend constituting the cutting edges of the blade.

'2. A cutting and grooving tool as in claim 1, resilient means supported by said post and having a part bearing against the bit shank for frictionally resisting sliding movement of the bit shank in said bore, and a feed screw threadedly mounted in an upper part of the tool post and having a lower end bearing against the upper end of the bit shank and cooperating with the resilient means to retain the blade in various adjusted positions.

3. A cutting and grooving tool as in claim 1, said cutting bit being supported by the tool post for positioning mediate portion combining with said bottom portionsto said cutting bit at an incline such that the front face of the blade is inclined upwardly and rearwardly, and said top wall opening including a portion disposed forwardly of the cutting bit and through which the cutting edges of the blade are visible when the tool is in an operative position.

References Cited in the file of this patent UNITED STATES PATENTS 535,191 Bretherton Mar. 5, 1895 620,226 C016 Feb; 28, 1899 1,031,509 Aylor July 2, 1912 1,307,151 Rowden et a1 June 17, 1919 1,825,859 Foy Oct. 6, 193l 2,013,893 Matthews Sept. 10, 1935 2,715,271 Carrier Aug. 16, 1955 FOREIGN PATENTS 4,233 Great Britain Feb. 27, 1893 

